This invention relates to a method of molding a hollowed portion, a raised portion, or a hollowed and raised portion in the body wall of a tubular container or a tube made of a synthetic resin, which is to be filled with a food, tooth paste, a cosmetic, and the like, and to a tubular container on which a hollowed and/or raised portion is formed.
Conventionally, tubular containers have been utilized to take out a given quantity of a viscous material, such as tooth paste. The bodies of these tubular containers comprise a tube obtained by extruding a synthetic resin in a cylindrical shape, or a tube of film with longer sides of the film joined together and adhered to each other. In many cases, laminated tubes are used, in which some resin layers are laminated.
A head consisting of neck and shoulder is adhered to one end of said tube, and the other end of the tube is thermally sealed. The finished product is used as a tubular container. Patent Document 1 has a description on a method of adhering the head to the tube.
As described above, the body of the tube is made and used by extruding a synthetic resin or resins in a cylindrical shape, or by joining and adhering longer sides of film together. In the case of ordinary tubular containers, the body is used in the flat, smooth state, without further processing. However, Patent Document 2 has descriptions on a surface-processed tubular container and on a method of producing such a tubular container. This method comprises utilizing an integrally joined tube prepared by rolling a synthetic resin sheet and thermally pressing together the overlap portions of the longer sides. When the lower end of the tube is heated and pressed for sealing, a pair of heating belts is used to emboss an up-and-down pattern from outside simultaneously with the sealing operation. It is asserted that this up-and-down pattern can be utilized for container recognition.
[Patent Document 1] Japanese Publication No. 1982-12739
[Patent Document 2] Japanese Application No. 1996-72905